Electric Vehicles (EV's), also referred to as an electric drive vehicle, uses one or more electric motors or traction motors for propulsion. Three main types of electric vehicles exist, those that are directly powered from an external power station, those that are powered by stored electricity originally from an external power source and range extended electric vehicles (serial hybrid) are propelled by an electric drivetrain powered by an electrochemical battery which is recharged by a small internal combustion engine (ICE) such as a generator or a hydrogen fuel cell to extend vehicle range when the energy in the storage device becomes sufficiently depleted. Parallel hybrid electric vehicles incorporate an ICE to assist the drivetrain.
All of the traditional engine driven accessory components, such as the power steering pump, air compressor and even the HVAC system, are now electrically powered, reducing energy consumption and further reducing greenhouse emissions. However, the combined electrical load required to operate these more efficient accessories still use more power than the drive system on a commercial vehicle and therefore have a dramatic limiting effect on electric vehicle range.
An Electric Vehicle Power Steering Pump Control System is needed to be able to efficiently manage accessory use and optimize charging opportunities, thereby maximizing vehicle driving range across a broad spectrum of vehicle speeds and driving conditions typically found in transit bus and freight delivery operations. The proposed Power Steering Pump Control System should also be capable of being integrated with a comprehensive adaptive power management and charging control system for optimal efficiency for electric vehicles.